package ch4;
//拖拉机
public class Tractor {
    double load,volume;//载重,体积
    public void show( double l,double v){
        this.load=l;
        this.volume=v;
    }
    public String nature(){
        return "载重"+load+"吨,体积"+volume+"立方";
    }
    public String  start(){
        return "启动";
    }
    public String  acceleration(){
        return "加速";
    }
}

